IS-IS Layer 2 mapping

You can enable Layer 2 mapping of next-hop addresses using the IS-IS LAN and point-to point Hellos that supply all relevant Layer 2 and Layer 3 binding address information for address resolution. The device at the receiving end can extract the information and populate the ARP or Neighbor Discovery table even before the installation of routes. Layer 2 mapping is a topology driven rather than traffic driven next-hop resolution that minimizes traffic loss while activating an Ethernet link.